Cellulose organic ester composition containing ethyl gamma-phenoxy butyrate



Patented Nov. 7, 1933 rssaszv 1,933,827 PnrEN OFF-ICE csrwtoss;oceanic E TE'KC P S I N CONTAINING GAMMA PHENOXY liUTYRA-T'E' Henry B: Smith; Rochester; assignor to Eastman- Kodak Company, Rochester, N. Y., a corporationof N ew, York Drawing;

a 7' claims; this-invention relates tocompositions of: matter in which cellulose organic esters, such as cellulose acetate, are combined or mixed with other substances, such as a compatible plasticizer, I? with or without a common solvent for both, and with Or -without other useful addition agents, so that the resulting product will have properties soon as will make the composition highly advantageous for use in the plastic and analogous arts; such; for instance, as the manufacture of wrapping sheets or tissue, photographic film,- moldlng compounds and molded products, artificial silk, varnishes or lacquers, coating compositioxi's and the like.

one object of this invention is to produce compositions of matter which may be made into varnishes, lacquers and the like, and to produce compositidns which will riotihjure', or be injured by, the substances or surfaces with which they 30 are associated during manufacture. Another ofiject of my invention is to produce compositions whichcan be' memes at elevated tempera tures andhigh pr'essures' t 'o produce plastic products-having the desirable properties" of celluloid; Still another object of my invention is to pro: duce compositions of matter containing cellulose acetatewhich have a high degree or flexibility, softnessand pliahilit y. Other objects will be- 46' which this invention'pertains.

While cellulose acetate has been known for" decades, it has also-been known that to utilize it in'the various plastic arts it; isnecessary to mix therewith various plasticizing or conditioning agent's-are also added for the purpose of reduc ing the inflammability orthe product. l lasti'c inducing agents, such as the higher alcohols and their esters, are sometimes also added. Similar- 50- 1y; addition compounds of various kinds have been employed to increase flexibility, transpar-' come apparent to those skilled in the art to agents. Certain of these and other addition pplication' February 4, 1933 Serial No. 655,261

(o1. me a the'art, the increasing use-to which cellulose acetate has been put andthe increasing number of desirable properties required of cellulose acetate for most purposes'have made the discovery of new and economical plasticizers or other and;

tion agents a matter of considerable importance to the' art. flhis has been a problem or" some difliculty, since manyof the nitrocellolose solvents arenot solvents f or cellulose acetate, and

manysubstances'which act as plasticizers for nitrocellulose are notcampatible or least" not sufiiciently compatible with cellulose acetate to be used as plasticizers in cellulose acetate compositions a I Ihavedi scovered that valuable properties may be induced in and/oricontributed to compositions containing organic esters of cellulose, such as celluloseacetate, byaddi ng thereto as a plasticizingv compound ethyl gamma-phenoaiybutyrate. This compound has the structural formula It may be prepared from gamma-phenokybutyric acid by' the usual methods of e's'terificat'i'o'nl The particularly useful properties which it induces in or contributes to cell ulosi c compositions contain ing it are hereinafter enumerated.

In order that those skilled in this art may better understand invention I would state, by way of illustration, that for the manufactureof pho tographic film base or other sheets my new campositionsloif matter may be" compounded as follows: 1({0 parts of acetone-soluble cellulose acetate, i. e. cellulose acetate containing from about 36% to 42% ac'etyl radical, approiriinately, is dissolved with stirring at atmospheric temperature in 300 1361500 parts, prefeiably 400 parts, by weight, of acetone. To" this solution may he addedfro'm lto G partsbywei'ght of ethyl garnma-phenox butyrate. Within the'limlts stated,- the amount of'plast'iciz er maybe decreased or in creased, depending upon whether it is desired to decrease or increase, respectivelylthe properties which these plasticizers ontrlblzteto'the finished product. The amourit'of stilvent employed" may also be increased or decreased,- dependingupon whether 'it' is desired'to have a more or less freely flowing com osition, respectively. f' A composition of matter prepared as above d'escribed may be deposited upon any suitable film forming surface and the acetone evaporated therefrom reform a' film or sheet, a manner Well known tothose skilled in the art. A film so" produced has permanently brilliant transparency and low inflammability, burning nomqre readily than ordinary aewsprme- Films o'r sheets'-producedin accordance withmy' invention are-tough and flexible. For instance, films of cellulose acetate plasticized with from to (10 to 50 parts by Weight based on the cellulose acetate) of ethyl gamma-phenoxybutyrate had an initial flexibility of from 65% to 600% greater than that of film containing no plasticizer. Furthermore,

, film so plasticized maintains flexibility in a su perior fashion. For instance, at 65 C. films con taining from to 50% of ethyl gamma-phenoxybutyrate maintained flexibilityfor over 150 days, whereas an unplasticized film became brittle in days. This indicates that films or sheets 10 so plasticized will withstand ordinary usage satisfactorily for many years.

Other similar solvents (instead of acetone) which are compatible with the cellulose acetate both the cellulosic derivative and the plasticiaer' being employed, such, for instance, as an alkylene chloride with or without the addition of alcohol. Inasmuch as my above-described compositions of matter are useful "in the production of films and sheets, it will be apparent that my new plasti- 30' 'cizer may also be employed with advantage in the other branches of the plastic art. For instance, my novel plasticizer may be employed with advantage in connection with a number of the known lacquer and varnish formula with which they may be found to be compatible. In such cases the plasticizer is usually first put into solution in the cellulose derivative solution, and if non-solvents are added for the purpose of cheapening the composition they are added only to such 40 an extent as will not precipitate the derivative from solution. Other uses within the scope of my invention will also suggest themselves to those skilled in'the art and are to be included within .the scope of the claims appended hereto. 4 Ethyl gamma-phenoxybutyrate may also be advantageously used as a plasticizer in cellulose organic ester molding compositions. when about 30% (30 parts by weight based on the cellulose acetate) of ethyl gamma-phenoxybutyrate is homogeneously mixed with cellulose acetate, the mixture may be converted into a hard, transparent or translucent plastic product by molding at a temperature of 140-160" C. and a pressure of 2500 to 4000 pounds per square inch for a period of from 2 to 5 minutes, in a manner already known to those skilled in" molding compounds of that nature.

Moreover, I have found that, upon the addition to cellulose acetate of approximately 100% of 0 ethyl gamma-phe'noxybutyrate, quite unexpected compatibility of the plasticizer with the cellulose acetateexists and also that quite unexpected flexability, plasticity and clarity of the final product result. Contrary to experience in most cases where such a large proportion of plasticizer is used, no exudation or crystallizing out of the plasticizer occurs. Compositions containing approximately 100% of ethyl gamma-phenoxybutyrate W have great utility where a highly flexible compound is desired, such as in the coating or a base (for instance, cloth or other fabric) in the pro- In like manner this plasticizer' For instance,

duction of artificial leather, or in the production of relatively thin sheets wherein more than the usual flexibility is important. Such a composition, if converted, for instance, into sheet form will be found to be supple and non-rigid, and to have the ability to conform readily to a surface upon which it may be placed, and this even at atmospheric temperatures.

These novel compositions of matter are produced by merely mixing the plasticizer with cellulose acetate and. then adding sufficient of a common solvent, such as acetone, whereupon an intimate mixture of the plasticizer with the cellulose acetate results. The amount of acetone or othercommon solvent to be employed varies, of -course,'within rather wide limits depending upon the fluidity of the composition desired. 100 parts of acetone will suffice for some purposes,, although I prefer to use 400 parts. Various high boilers or evaporation retardents, such as ethyl lactate, amyl acetate or the like mayalso beadded if desired, as is well known in this art. The-compositions of matter so produced may then be coated into sheets in the usual way by depositing them upon plates or rolls and permitting the solvent to evaporate. If my' novel'compositions are to be employed in themanufacture of artificial leather, they, may be coated upon, for instance, a cloth support and the solvent permitted to evaporate, or the cloth support may 0 be caused to pass through the cellulose acetateplasticizer composition and permittedto absorb the soluton, the solvent in the coating being then permitted to evaporate. In either case, the solvent may, of course, be recovered if desired by 0 condensing the vapors, etc.

While above and in certain of the claims appended thereto, I have referred to the use of a plasticizer in approximately equal proportions, namely in a ratio of approximately 100%, it will be understood that within this terminology variations of from 10% to 15% less than 100% of plastiCizer and as much as 25% to 50% more than 100% of the plasticizer may in some instances be desirable.

What I claim as my invention and desire to be, secured by Letters Patent of the United States is:

1. A composition of matter comprising a cellulose organic ester and ethyl gamma-phenoxybutyrate. v

2. A composition of matter comprising cellulose acetate and ethyl gamma-phenoxybutyrate.

3. A composition of matter comprising 100 parts of cellulose acetate and about 10 to '100 parts, by weight, of ethyl gamma-phenoxybutyrate.

4. A transparent, flexible sheet comprising 100 parts of a cellulose organic ester and about 10 to 50 parts, by weight, of ethyl gamma-phenoxybutyrate.

5.. A transparent, flexible sheet comprising 100 135 parts of cellulose acetate and about 10 to 50parts, by weight, of ethyl gamma-phenoxybutyrate.

6. A molding composition adaptedfor molding under elevated temperatures and high pressures, comprising a cellulose organic ester and ethyl gamma-phenoxybutyrate.

v 7. A molding composition adapted for molding under elevated temperatures and high pressures, comprising cellulose acetate and ethyl gammaphenoxybutyrate.

HENRY B. SMITH. 

